首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   31676篇
  免费   1581篇
  国内免费   158篇
耳鼻咽喉   467篇
儿科学   571篇
妇产科学   342篇
基础医学   4276篇
口腔科学   812篇
临床医学   2108篇
内科学   7970篇
皮肤病学   789篇
神经病学   2048篇
特种医学   1285篇
外国民族医学   1篇
外科学   5318篇
综合类   170篇
一般理论   2篇
预防医学   882篇
眼科学   401篇
药学   2361篇
中国医学   108篇
肿瘤学   3504篇
  2023年   165篇
  2022年   350篇
  2021年   556篇
  2020年   329篇
  2019年   435篇
  2018年   520篇
  2017年   455篇
  2016年   552篇
  2015年   537篇
  2014年   762篇
  2013年   901篇
  2012年   1464篇
  2011年   1581篇
  2010年   890篇
  2009年   858篇
  2008年   1426篇
  2007年   1630篇
  2006年   1538篇
  2005年   1639篇
  2004年   1554篇
  2003年   1404篇
  2002年   1374篇
  2001年   1076篇
  2000年   1009篇
  1999年   979篇
  1998年   399篇
  1997年   282篇
  1996年   323篇
  1995年   243篇
  1994年   195篇
  1993年   228篇
  1992年   656篇
  1991年   566篇
  1990年   554篇
  1989年   562篇
  1988年   535篇
  1987年   495篇
  1986年   472篇
  1985年   437篇
  1984年   329篇
  1983年   264篇
  1982年   168篇
  1979年   248篇
  1977年   188篇
  1973年   178篇
  1972年   188篇
  1971年   190篇
  1970年   173篇
  1969年   189篇
  1968年   173篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
A 52-year-old woman who developed acute transverse myelopathy following systemic lupus erythematosus (SLE) was reported. At the age of 46, she was diagnosed as having atypical psychosis. Neurological examination revealed mild depressive state, paraparesis, diffuse hyperreflexia, hypesthesia below the breasts, and urinary disturbance. Gait was slightly ataxic and Romberg sign was positive. Laboratory study disclosed lymphocytopenia, positive antinuclear antigen, false positive Venereal Disease Research Laboratories flocculation test and prolonged activated partial thromboplastin time. IgG anticardiolipin antibody (aCLA) was positive, whereas IgM aCLA was negative. Cerebrospinal fluid was normal except the elevation of %IgG. Nerve conduction studies were normal and no abnormality was detected in the brain and spinal cord by MRI and CT. We treated her by two series of steroid pulse therapy, which resulted in marked improvement of symptoms and disappearance of aCLA. Before and after the pulse therapy, symptoms were fluctuated in parallel with the levels of aCLA. These findings suggest the relation of aCLA to the transverse myelopathy in SLE. This is the first case report of a good prognosis of myelopathy in a SLE patient who was treated by steroid pulse therapy with the aim of disappearance of aCLA.  相似文献   
33.
This study was performed to examine the pattern of Superoxide (O 2 ·) generation from leukocytes using the O 2 · specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O 2 · generation by leukocytes. The time course of O 2 · generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O 2 · for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O 2 · generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O 2 · much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O 2 · generation by leukocytes.  相似文献   
34.
35.
36.
37.
Repeated injections of 45 ng/kg of maitotoxin into the peritoneal cavities of male ICR mice resulted in marked atrophy of lymphoid tissues, a reduction of lymphocytes in the circulating blood, reduced immunoglobulin M in serum, and an increase of calcium content in the adrenal glands. A single injection of 200 ng/kg of maitotoxin induced a marked increase in total calcium content of the adrenal glands as well as in plasma cortisol concentration (about seven times control) within 1 hr. In contrast, mice pretreated with CoCl2, a calcium channel inhibitor, and/or adrenalectomized mice, showed no discernible changes in the lymphoid tissues after repeated injections of maitotoxin. It is thus suggested that maitotoxin first stimulates calcium influx in the adrenal glands, which then causes the release of cortisol into the blood. The excess amount of cortisol in serum produces acute involution of the thymus and other lymphoid tissues.  相似文献   
38.
A 36-year-old man was admitted to a hospital with complaints of fever, polyarthralgia and dyspnea. Erythema was observed on his face, extensor surface of the fingers and extremities, and a chest X-ray revealed massive bilateral pleural effusion. He had no sign of myopathy at this point. Pleural fluid was proved to be exudative and contained extremely high levels of hyaluronic acid. He was also complicated with interstitial pneumonitis and was given a pulse therapy with methyl prednisolone followed by daily administration of 55 mg prednisolone (PSL). Twenty days after the commencement of the therapy, pleural effusion decreased but muscle weakness gradually appeared, accompanied by elevation of myogenic enzymes. Myogenic changes on electromyogram, and irregularity of the muscle fibers with slight inflammatory cell infiltrates in a biopsy specimen were demonstrated. He was transferred to our hospital, and a diagnosis of dermatomyositis was made. Later, pleural effusion waxed and waned depending on the dosage of PSL, but no other causative disorder was demonstrated by extensive examinations. This case indicates that the pleuritis could be one of the vasculitic manifestations of dermatomyositis.  相似文献   
39.
40.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号